Infantile systemic Hyalinosis in a 6-month-old male: identification of homozygous ANTXR2 gene mutation.

Abstract

This case report presents a 6-month-old male infant with a diagnosis of infantile systemic hyalinosis (ISH) and describes the diagnostic difficulties and findings of clinical examinations, laboratory analyses, and imaging studies. A 6-month-old male infant was admitted with abdominal distension, persistent diarrhea, and joint tenderness. His history included profuse watery diarrhea and a hospitalization for hypoalbuminemia. Upon arrival, he presented with multiple episodes of non-bloody diarrhea, oxygen desaturation, and signs of failure to thrive. Physical examination revealed joint swelling, spasticity, failure to thrive, short stature and developmental delays. Imaging studies including abdominal and pelvic ultrasound showed free fluid, intestinal distension, and renal microlithiasis. Imaging results included a chest X-ray showing mild interstitial markings and a brain MRI showing dilatation of subarachnoid space. Laboratory studies demonstrated an elevated white blood cell count (13 300 cells/mm³), high levels of ammonia, and relatively low hemoglobin. Ultimately, the diagnosis of ISH was confirmed by a homozygous ANTXR2 gene mutation. This case accentuates the need for an integrated approach to the diagnosis of nonspecific infant symptoms. Diagnosis should be made early and accurately with a high index of suspicion; it forms the cornerstone for any treatment or prevention of complications. Furthermore, the early recognition of ISH is important in effective management and family counseling with the aid of genetic analysis. The findings add to the knowledge about ISH and its clinical implications, pointing to the need for continued research into rare genetic disorders.